A network management and control simulator (NEMACS) software testbed for developing, testing, and integrating different network management (NM) techniques for multiservice circuit-switched networks is discussed. NEMACS is capable of applying different NM strategies to a plethora of simulated network scenarios that include networks of differing size, speed, transport topology, control, and management architectures. NEMACS simulates networks by modeling the behavior of various network modules: call transport modules (CTMs), call control modules (CCMs), and network control modules (NCMs). The implementation of NEMACS software and four examples of how NEMACS has been used to rapidly prototype NM techniques are presented. The examples deal with focused overload in a simple network, predictive access-control and routing strategy, decentralized management, and multiclass traffic control. >